Cellulose recovery from BRASPOLPA: A semi-solid residue generated in the process of citrus pectin extraction

• Grant number: 23/07568-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): August 01, 2023
• Effective date (End): July 31, 2024
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Organic Chemistry
• Principal Investigator: Ljubica Tasic
• Grantee: Matheus Signorelli Correa
• Host Institution: Instituto de Química (IQ). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

Citrus fruits are the most consumed and processed fruits worldwide, especially oranges, which have the majority of their production destined for juice production, generating a large amount of waste. This biomass generated from orange processing is abundant in chemical compounds such as proteins, starch, soluble sugars, lipids, lignin, pectin, and cellulose, which have high added value in the market. These waste materials have an average of 20-30% pectin, a biopolymer mainly composed of galacturonic acid (GalA) units linked by glycosidic bonds of type -1-4. Therefore, the main source of this biopolymer in the market is currently citrus waste. Companies such as CP Kelco Brazil S.A. explore citrus waste for pectin extraction and commercialize Genu pectin. However, during the pectin extraction process, new waste materials are generated, which have a high content of biopolymers such as cellulose, as it is used during the pectin extraction process. Cellulose, a homopolysaccharide composed of D-glucose units, has various applications in different industrial sectors such as food, biomedicine, cosmetics, pharmaceuticals, and biofuels. Due to the importance of this biopolymer in the industry, it will be the focus of study in this project. Thus, the objective of this work will be to evaluate extraction conditions for cellulose from BRASPOLPA, a semi-solid residue from the citrus pectin extraction industry, and from fresh orange peels, in order to obtain a more efficient extraction. To evaluate the best conditions (extractor concentration, temperature, solid-liquid ratio, among others), the yield and purity of the cellulose obtained in each extraction will be considered. Cellulose will be characterized using methods such as infrared spectroscopy (FT-IR), solid-state nuclear magnetic resonance of ¹³C (CP/MAS NMR), electron microscopy, and X-ray diffraction. Multivariate calibration models will be constructed to determine the best extraction conditions.